1. Field of the Invention
The present invention relates generally to a multi-segment rotary shaft structure, and more particularly to a multi-segment rotary shaft structure applicable to an electronic device. The multi-segment rotary shaft structure has multiple rotational centers so that the rotational freeness of the electronic device is enhanced and two ends of the electronic device can be more smoothly rotated and opened or closed.
2. Description of the Related Art
With a notebook or the like electronic device taken as an example, the notebook is generally composed of a base seat as a system end and an upper cover as a display end. The base seat and the upper cover are pivotally connected with each other via a pivot device, whereby the upper cover can be lifted open around the pivot device for use or reversely closed onto upper surface of the base seat. The pivot device is quite important in that it not only serves as a rotational center of the electronic device, but also needs to provide sufficient support force for locating the display screen of the upper cover in a desired operation angular position, (which is generally 135 degrees with respect to a notebook).
The above conventional pivot device generally includes an assembly having a shaft and an assembly having a sleeve. One of the assemblies is installed on the upper cover, while the other of the assemblies is installed on the base seat with the shaft fitted in the sleeve. In consideration of the support structural strength and operational smoothness, in general, two sets of pivot devices each including a shaft and a sleeve are disposed on two sides of the junction between the upper cover and the base seat of the electronic device (such as a notebook).
The axes of the shafts of the two pivot devices often fail to coincide with each other. Therefore, it often takes place that the upper cover of the electronic device can be hardly coordinately rotated open. Moreover, the rotational freeness of the pivot devices nearly positioned in the same central line is limited. As a result, the upper cover of the electronic device can be hardly smoothly rotated and opened or closed.